1. Field of the Invention
The present invention relates to an inkjet recording apparatus that ejects ink onto a recording sheet to perform recording, and more particularly to an inkjet recording apparatus that reduces a reduction in throughput of printing.
2. Description of the Related Art
A recording apparatus, such as a printer, copying machine, and facsimile, is configured to record an image composed of a dot pattern onto a recording material such as paper or a plastic thin plate based on image information.
The recording apparatus can be classified into an inkjet type, wire dot type, thermal type, laser beam type, etc., according to a recording system. The inkjet type (inkjet recording apparatus) of these systems is configured to record an image by ejecting an ink (recording liquid) droplet from an ejection port of a recording head and allowing the ink droplet to be deposited onto the recording material.
Most of the inkjet recording apparatuses record an image using aqueous liquid ink. Therefore, after an image is formed, a recording sheet extends due to moisture contained in the ink, so that a paper fiber on a surface where the image is formed expands to produce a phenomenon in which the recording sheet is curled. When the curl is generated, discharged recording sheets might not be aligned or paper jam might be produced.
Japanese Patent Application Laid-Open No. 8-267846 discusses that, to solve the situation, a time taken for drying the ink is obtained according to a temperature, humidity, and a printing ratio, conveyance of the recording sheet after the image formation is temporarily stopped until the drying time is elapsed, and then, the recording sheet is discharged after the lapse of the drying time.
Alternatively, Japanese Patent Application Laid-Open No. 2005-246727 discusses that a mode is changed to a mode in which a paper feeding amount is relatively small according to drying time to provide the drying time, to prevent a discharged recording sheet from being curled.
Japanese Patent Application Laid-Open No. 7-205416 discusses a method in which, to provide drying time while keeping reduction in a printing speed to a minimum, a printing ratio is detected for every predetermined area and the drying time is obtained according to the printing ratio to keep the drying time to a minimum.
However, the recording apparatuses discussed in above described Japanese Patent Applications Laid-Open No. 8-267846, No. 2005-246727, and No. 7-205416 obtain ink drying time according to a temperature, humidity, and printing ratio for every predetermined area. Therefore, these apparatuses do not sufficiently reflect change in the drying time according to various conditions such as a recording mode or paper feeding structure of these apparatuses, and hence, they take much recording time in total than necessary.